Condition monitoring is an important tool for detecting faults and adverse operating conditions of rotating machine parts, such as bearings, thereby making it possible to carry out preventive maintenance or repairs before any major failure occurs. It is particularly important in remote installations like wind turbines, which operate without supervision and where critical failures are extremely expensive to repair.
An example of condition monitoring of an epicyclic gearbox in a wind turbine is disclosed in U.S. Pat. No. 8,393,993. The gearbox has at least two planet gears, each of which is rotationally supported on a planet gear shaft by a bearing. The gearbox further has at least one planet carrier that connects the planet gears. The planet carrier is provided with one or more sensors, including a vibration sensor. In an embodiment, the planet carrier is provided with a vibration sensor placed on or in close proximity to each of the planet gear shafts.
The sensor is therefore located relatively far away from the bearing that supports the planet gear shaft, meaning that vibrations associated with bearing defects are more difficult to detect.